A wide variety of electromagnetic motor constructions are known in the art, as exemplified by those shown in U.S. Pat. No. 3,292,023 issued Dec. 13, 1966 to Kober, U.S. Pat. No. 4,025,807 issued May 24, 1977 to Clover, U.S. Pat. No. 4,020,372 issued Apr. 26, 1977 to Whiteley, U.S. Pat. No. 3,992,642 issued Nov. 16, 1976 to Heinrich et al., U.S. Pat. No. 3,983,430 issued Sept. 28, 1976 to Howard, U.S. Pat. No. 4,037,124 issued July 19, 1977 to Kullmann et al., U.S. Pat. No. 3,845,339 issued Oct. 29, 1974 to Merkle et al., U.S. Pat. No. 3,428,840 issued Feb. 18, 1969 to Kober, U.S. Pat. No. 3,445,691 issued May 20, 1969 to Beyersdorf et al., U.S. Pat. No. 3,277,323 issued Oct. 4, 1966 to Parker, U.S. Pat. No. 2,782,721 issued Feb. 26, 1957 to White, and U.S. Pat. No. 3,223,043 issued Dec. 14, 1965 to Shapiro.
Prior art motors are characterized by their relative complexity and by undesirable variations in speed caused by electric motor impulses when the motors are scaled up in size. In addition, cooling has been a problem, often requiring expensive cooling systems used in conjunction with the motor to attain adequate heat dissipation and removal. Because of their bulk, many of the prior art devices do not readily lend themselves to being utilized on a common drive shaft with other prime mover mechanisms of like construction.